The invention relates to an explosion-resisting window with a window frame and a sash frame, which accommodates a panel and is mounted in hinges on the window frame, so as to be tiltable around at least one axis, the sash frame nesting in the window frame in closed position.
“Tiltable” and “tilting” within the meaning of the present application are to be understood as turning between swiveling of the window frame around an arbitrary axis. In this application, the meaning of the term “tilting” encompasses not only classical “tilting” around a horizontal axis of rotation at the bottom of the sash frame but also, for example, “tipping” around a horizontal axis of rotation at the top of the sash frame or “turning” around a vertical axis of rotation. In particular, all combined tilt-and-turn windows are intended to fall within the scope of protection of the present application.
A window of the type described hereinabove is known from German Patents 3420883 C2 and 3432021 C2, for example. The two already known window constructions are designed as double windows. Therein there is disposed, in front of the actual window, which is provided with a window frame and a sash frame mounted pivotally therein, a further fixed glazing. Between the fixed glazing and the window bay there are disposed connecting cross sections to the intermediate space between the two glazings and the window bay, so that, in the case in which the sash frame of the inner glazing is opened, a certain air circulation can take place through the double glazing.
The object of the double glazing is to attenuate the effect of a detonation on the outside of the building to the extent that the persons present in the building suffer no injury if at all possible. Because of the openings between the edge of the outer glazing and the window bay, pressure equalization takes place in the event of an explosion shock, and so the pressure developed during the explosion may indeed be capable of destroying the outer glazing, but thereby the pressure spike is dissipated, with the result that the maximum pressure cannot act on the inner glazing, since the openings make it impossible for compression of the air inside the space between the two glazings to reach a hazardous level. Thus it is possible to provide the inner glazing with a swivelable or pivotally movable sash frame inside the window frame, so that the openings provided specifically for pressure relief between the outer glazing and the window bay can be used for ventilating the room.
The already known window construction can be regarded as suffering from disadvantages, in the first place because the manufacturing costs for the two glazings are comparatively high. In the second place, the outer glazing, which is usually destroyed in the event of a detonation, then represents a not inconsiderable danger for the persons present in the building, if the sash frame of the inner glazing is in its opened position. In this particular case, glass splinters can fly through the opened sash frame into the room interior, thus causing a not inconsiderable risk of injury. Moreover, the danger exists that, if the sash frame is wide open, the pressure rise in the interior of the building after the outer glazing has burst is still so great that persons suffer injury as a result. In principle, therefore, an adequate level of safety for persons present in the room is assured only if the sash frame of the inner glazing is in its closed position.